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11000 miles? (4, Informative)

CrimsonAvenger (580665) | about 5 months ago | (#46319489)

The Lunar equator is 11,000 Kilometers long.

Re:11000 miles? (0)

Anonymous Coward | about 5 months ago | (#46319731)

William Waldon has not learned from the Mars Climate Orbiter.

Re:11000 miles? (4, Funny)

JWSmythe (446288) | about 5 months ago | (#46319983)

Miles, kilometers, what's it matter. It's not rocket science... ... oh ...

Re:11000 miles? (1)

Jeremiah Cornelius (137) | about 5 months ago | (#46320015)

That's no moon. It's a space station...

Re:11000 miles? (5, Informative)

Anonymous Coward | about 5 months ago | (#46320133)

Yes, I don't however see any data on their website about how wide they are planning to build the ring out. If their graphical renderings are accurate, they display a 195 pixel moon with a 22 pixel ring. Given that google tells me the moon's radius is 1737 km, that means the ring should be about 200 km wide.

So considering that we have a 11,000 km ring that is 200 km width, the power generation for the light-facing half should be what you'd expect from 5500km x 200km or 1,100,000 square kilometers. I've seen estimates of 1.2 mw per square km for solar [youthkiawaaz.com] . Using that as a basis we'd expect 1,320,000 mw of constant power generation. Wikipedia says to take off 10% due to conversion inefficiencies of microwave transmission of electricity [wikipedia.org] and we probably should take off another 5% or so for weather and atmospheric disruptions or inefficiencies. That leaves us with 1,122,000 mw of constant power.

As a point of comparison, all the wind power in the entire world added up to 238,351 megawatts in 2011 [wikipedia.org] , so it is roughly five times the capacity of that. However, in 2008 the world had an average power consumption rate of 15 terawatts [californiaphoton.com] . 1,122,000 mw is 1.12 terawatts, so this project could supply roughly 7% of the worlds electricity if it was operational today.

The moon has an area of 37,932,000 square km though, so if we coated the entire moon and got energy from the sunny side and do the same math we get 19.34 terrawats. So, at our current state of energy usage it could power the world if we coated the moon in solar panels.

I'm not sure about the aesthetics of it though, a racing stripe on the moon.

Moon Ring Math (3, Interesting)

neoshroom (324937) | about 5 months ago | (#46320163)

Yes, I don't however see any data on their website about how wide they are planning to build the ring out. If their graphical renderings are accurate, they display a 195 pixel moon with a 22 pixel ring. Given that google tells me the moon's radius is 1737 km, that means the ring should be about 200 km wide.

So considering that we have a 11,000 km ring that is 200 km width, the power generation for the light-facing half should be what you'd expect from 5500km x 200km or 1,100,000 square kilometers. I've seen estimates of 1.2 mw per square km for solar [slashdot.org] . Using that as a basis we'd expect 1,320,000 mw of constant power generation. Wikipedia says to take off 10% due to conversion inefficiencies of microwave transmission of electricity [wikipedia.org] and we probably should take off another 5% or so for weather and atmospheric disruptions or inefficiencies. That leaves us with 1,122,000 mw of constant power.

As a point of comparison, all the wind power in the entire world added up to 238,351 megawatts in 2011 [wikipedia.org] , so it is roughly five times the capacity of that. However, in 2008 the world had an average power consumption rate of 15 terawatts [californiaphoton.com] . 1,122,000 mw is 1.12 terawatts, so this project could supply roughly 7% of the worlds electricity if it was operational today.

The moon has an area of 37,932,000 square km though, so if we coated the entire moon and got energy from the sunny side and do the same math we get 19.34 terrawats. So, at our current state of energy usage it could power the world if we coated the moon in solar panels.

I'm not sure about the aesthetics of it though, a racing stripe on the moon.

I think I've seen this plan (5, Funny)

cold fjord (826450) | about 5 months ago | (#46319493)

Collect massive amounts of power, and beam it towards a planet. What could possibly go wrong?

In a surprise vote at the UN, the General Assembly accepted a proposal from Krasnovia to rename the planet. The new name is "Alderaan."

Re:I think I've seen this plan (2)

Cryacin (657549) | about 5 months ago | (#46319553)

I suspect it would be more like sim city's microwave receivers. A few buildings getting a little glow in the dark is hardly an Alderaan. Leave that one to the Chinese!

Re:I think I've seen this plan (1)

houstonbofh (602064) | about 5 months ago | (#46319595)

Collect massive amounts of power, and beam it towards a planet. What could possibly go wrong?

If you think people are nuts about global warming now...

Re:I think I've seen this plan (2)

ShanghaiBill (739463) | about 5 months ago | (#46319769)

Collect massive amounts of power, and beam it towards a planet. What could possibly go wrong?

If you think people are nuts about global warming now...

Global warming is not caused by adding heat, but by changing the rate of heating, or dh/dt.
Putting solar panels on the moon seems silly. They would collect twice the energy if they were placed in orbit. According to TFA, the materials would come from earth, so why go to extra effort to take them down to the lunar surface, halving their effectiveness? Also, what happens when there is a lunar eclipse?

Re:I think I've seen this plan (4, Funny)

cold fjord (826450) | about 5 months ago | (#46319821)

Also, what happens when there is a lunar eclipse?

Not much, in North Korea [yahoo.com] .

Re:I think I've seen this plan (0)

Anonymous Coward | about 5 months ago | (#46319845)

cold fjord has a sense of humor...who knew?

well done, sir.

Re:I think I've seen this plan (1)

bigfinger76 (2923613) | about 5 months ago | (#46319923)

I'd mod this funny...

Re:I think I've seen this plan (1)

phantomfive (622387) | about 5 months ago | (#46319857)

They would collect twice the energy if they were placed in orbit.

Why? They would be outside the atmosphere in both scenarios.

Of course, the moon seems ridiculously more expensive, but whatever.

Re:I think I've seen this plan (0)

Anonymous Coward | about 5 months ago | (#46319941)

They would collect twice the energy if they were placed in orbit.

Why? They would be outside the atmosphere in both scenarios.

Srsly? You don't know why?

Okay, I'll give you a hint: the moon rotates too.

Re: I think I've seen this plan (0)

Anonymous Coward | about 5 months ago | (#46320135)

Our moon does not rotate.

Re:I think I've seen this plan (1)

quenda (644621) | about 5 months ago | (#46319949)

They would collect twice the energy if they were placed in orbit.

Why? They would be outside the atmosphere in both scenarios.

In orbit, you don't have a big rock blocking the sunlight half the time.

Re:I think I've seen this plan (4, Insightful)

icebike (68054) | about 5 months ago | (#46319999)

They would collect twice the energy if they were placed in orbit.

Why? They would be outside the atmosphere in both scenarios.

The 11000 KM in the article referred to the circumference of the moon. The (harebrained) scheme postulates
putting the photoarray entirely around the moon at its equator (on the surface).

Only half of that circumference is facing the sun at any given time.
Only about 2/3s of that half would have anything near an optimal angle to the sun.

By placing steerable arrays in earth orbit, you gain the ability to keep ALL of them always angle toward the sun.

Re:I think I've seen this plan (1)

AK Marc (707885) | about 5 months ago | (#46320175)

So what orbital pattern results in the Earth never eclipsing the sun?

Re:I think I've seen this plan (1)

suutar (1860506) | about 5 months ago | (#46320013)

I think his theory is that at any time, only half of the moon is in sunshine, whereas if the panels were in orbit they could be placed to always be in sunshine. It seems to me that having them on the moon might (emphasis on might) make maintenance somewhat easier, and as long as there's enough panel area in the lit half, it's good enough, but as he says paying for both a lit half and an unlit half adds up.

Re:I think I've seen this plan (2)

phantomfive (622387) | about 5 months ago | (#46320101)

Why would anyone put solar panels on the dark side of the moon?

Re:I think I've seen this plan (2)

phantomfive (622387) | about 5 months ago | (#46320105)

nevermind, I just realized I wasn't thinking

Re:I think I've seen this plan (1)

gd2shoe (747932) | about 5 months ago | (#46319869)

Really...?

First, I'm not sure what to think about the climate change political debate (which has so thoroughly obscured good science through funding bias - in both directions - and social pressure as to make actual scientific discussion practically impossible). So I'm only going to parrot for a bit.

It is all about heat, both change AND absolute. The planet is a complex system that deals with fluctuating carbon quite nicely. But those subsystems only operate well at particular temperatures. As the absolute temperature increases, less carbon gets sequestered, and green house gasses that are already sequestered get released. Thus, absolute heat drives a change in heat.

Or at least, the very loud theories say this. IANAC

Re:I think I've seen this plan (1)

CrimsonAvenger (580665) | about 5 months ago | (#46319939)

They would collect twice the energy if they were placed in orbit. According to TFA, the materials would come from earth, so why go to extra effort to take them down to the lunar surface, halving their effectiveness?

More like three times as effective in orbit.

On the other hand, once you get reach the point of making the structural elements from lunar aluminium, you reduce the amount of material to be lifted from Earth.

Also, what happens when there is a lunar eclipse?

Not much. A couple hours every few years doesn't amount to much power loss, really.

Biggest problem is that until you have the solar collectors completely circling the moon, you'll be producing power not much more than half the time, at best.

Re:I think I've seen this plan (3, Interesting)

Immerman (2627577) | about 5 months ago | (#46319955)

I think the article is mistaken, or at least very, very badly phrased. Perhaps "Earthly materials" was a mistranslation of "common materials"? Even TFA says water won't be taken to the moon for construction, instead only hydrogen which will be reacted with lunar oxygen to produce water. And if they need water for construction... well presumably they're talking full on manufacturing. The video offers no useful insights either.

Right on with the global warming bit - for (minimal) added reference I tracked down the numbers a while back, and IIRC the incremental greenhouse effect of one year's fossil fuel CO2 emissions is responsible for trapping something like millions of times as much energy as was contained in the fuel. And that's just in the first year, it will continue to do the same for many decades to come until eventually recaptured by the carbon cycle.

Re:I think I've seen this plan (2)

ClickOnThis (137803) | about 5 months ago | (#46319959)

Putting solar panels on the moon seems silly. They would collect twice the energy if they were placed in orbit.

I'm not sure about the factor of 2. In earth orbit, you'd still have at least some satellites being eclipsed by the earth on a regular basis.

Perhaps it's better to put them at earth-sun lagrangian points. [wikipedia.org] They'd still be eclipsed by the moon occasionally, but only parts of the earth would be blocked at any moment during the event. Of course, you'd need to burn more fuel to get there, and additional fuel consumption to maintain the lagrangian orbits would cut down on the useful lifetime of the satellites.

According to TFA, the materials would come from earth, so why go to extra effort to take them down to the lunar surface, halving their effectiveness?

Agreed. It would only make sense to put them on the moon if you could manufacture the panels there.

Re:I think I've seen this plan (1)

AK Marc (707885) | about 5 months ago | (#46320161)

Putting solar panels on the moon seems silly. They would collect twice the energy if they were placed in orbit.

Why is that? The moon has no atmosphere to get in the way.

According to TFA, the materials would come from earth,

The article is wrong and contradicts the official materials by the company in question.

Also, what happens when there is a lunar eclipse?

Power output will be lower for a few hours every 6 months or so. Doesn't sound like a big issue.

Re: I think I've seen this plan (1)

Nodsnarb (2851527) | about 5 months ago | (#46319787)

'That's no moon...it's a space station!'

Re:I think I've seen this plan (0)

Anonymous Coward | about 5 months ago | (#46320023)

This was in Simcity 2000, the natural disaster was called "OOPS"

Literately, microwave power plant (though I think it was an orbital man-made satellite, not a moon-is-a-satellite thing.)

Also from a technical perspective, this is incredibly possible to do. Misalignment of the power receiving station is likely to damage surrounding infrastructure. So the plants would likely be unmanned in a similar way a nuclear plant is unmanned, mainly just to prevent being cooked to death if the plant works too well.

Old Popular Mechanics columnists don't die ... (1)

140Mandak262Jamuna (970587) | about 5 months ago | (#46319509)

..They become Shimizu's Dream corporation staffers.

abitious (0)

Anonymous Coward | about 5 months ago | (#46319523)

maybe look ambitious but i'm sure they will succes with they technology. Coz japan is awsome

http://omjes.info

Re:ambitious? (2)

Spottywot (1910658) | about 5 months ago | (#46319567)

I remember having this conversation in Physics class many years ago, would be fantastic if it goes ahead but I honestly don't think that anyone would invest the huge amount of money needed to even attempt this, at least not until the oil has run out.

Re:ambitious? (1)

skids (119237) | about 5 months ago | (#46319713)

I would say that only the Japanese would think surface area here on Earth to be at such a premium that it would be worth it versus panels here on Earth.

I would, except for the slew of other people who have proposed lifting them into orbit.

I view all such proposals as a distraction from the real logistics issues involved in installing more of the renewables we can build now and connect to the power grid by more conventional means, with the added whimsical notion that what they really want is a death ray.

Re:ambitious? (1)

Immerman (2627577) | about 5 months ago | (#46320005)

> I view all such proposals as a distraction...
So do I for the most part - but maybe not for Japan. After all they don't really have the land area to do much in the way of renewables themselves, are subject to tropical storms which make offshore source problematic, and they aren't exactly on the best terms with their neighbors.

Plus there's the fact that such a system could very easily be modified into a terrifying weapon, which could do a great deal for the national security of a tiny island nation off the shore of a hostile up-and-coming superpower. I doubt they want to be the US's political lapdogs forever.

Re:ambitious? (1)

garyisabusyguy (732330) | about 5 months ago | (#46320041)

This proposal would only make sense if you planned on using the first few missions to establish the ability to turn local Lunar resources into solar panels

On the other hand, an orbital system would have to lift well... how much?

current solar panels weigh 15.8 kg/m^2, lets make life simple and imagine that they can make solar panels that are 1kg/m^2
and the moons equator is 11,000 Km (I can;t believe that the story said that it was miles...) and lets say they decide to make it a Km wide that is
11 billion kg of mass you are putting into orbit to match the generating ability of the lunar system

Ouch, that is a big win for a Lunar system right there... Even if you could get a solar film in space that was down to a gram per square meter, that is still 11 million kg... or 460 shuttle launches ouch!

Re:ambitious? (3, Informative)

InterGuru (50986) | about 5 months ago | (#46319817)

After the oil runs out, there won't be any money. Details here [ourfiniteworld.com] . Warning -- it's a harrowing read.

Timely news source for technology related news... (5, Funny)

Buck Feta (3531099) | about 5 months ago | (#46319541)

s/Timely/oldAsFuck/. Hilarious when Huffington Post beats Slashdot to a story [huffingtonpost.co.uk] by two and a half months.

Re:Timely news source for technology related news. (1)

ColdWetDog (752185) | about 5 months ago | (#46320147)

They don't have to worry about beta software. Besides, it takes about this long to allow for our in depth analysis and witty repartes.

SimCity 2000! (1)

Anonymous Coward | about 5 months ago | (#46319547)

I remember in that game you could build a microwave power plant that got its power from something orbiting the planet or on the moon. Occasionally it would misalign and blow away a few city blocks of stuff.

Re:SimCity 2000! (2)

master5o1 (1068594) | about 5 months ago | (#46319703)

Simple solution is to turn disasters off.

Re:SimCity 2000! (1)

SJHillman (1966756) | about 5 months ago | (#46319753)

You assume the AC was saying that blowing away a few city blocks was a bad thing. I believe it's necessary to keep those Sims from becoming uppity.

Solving the wrong problem (0)

Anonymous Coward | about 5 months ago | (#46319549)

We already have plenty of sunlight right here on earth. That isn't the problem. The problem is how to gather, store, and use it. Solving those problems on the earth would be better than solving them on the moon

Re:Solving the wrong problem (2)

Buck Feta (3531099) | about 5 months ago | (#46319625)

Actually the problem is that Earth-based solar collection is terribly inefficient. A solar cell (15 - 20% efficient to begin with), fixed to one spot on the Earth, is exposed to sunlight for a fraction of a day, sunlight which has been diffused by the Earth's atmosphere. Extraplanetary collection is actually a very good idea.

Re:Solving the wrong problem (1)

FrankSchwab (675585) | about 5 months ago | (#46319673)

And a solar cell fixed to one spot on the moon is exposed to sunlight for more than a fraction of a day?

We're not talking orbital solar panels here.

Re:Solving the wrong problem (0)

Anonymous Coward | about 5 months ago | (#46319683)

yes.. did you not know that the moon is always sunny on one side and always shaded on the other side?

Re:Solving the wrong problem (2)

Blaskowicz (634489) | about 5 months ago | (#46319815)

Do you know about moon phases?

Re:Solving the wrong problem (0)

Anonymous Coward | about 5 months ago | (#46319883)

Did you know that it's possible to have multiple transmitters at various places on the moon?

Re:Solving the wrong problem (1)

viperidaenz (2515578) | about 5 months ago | (#46319969)

Did you know that it's possible to have multiple solar panels at various places on the Earth?

Re: Solving the wrong problem (0)

Anonymous Coward | about 5 months ago | (#46319853)

Really? You're both wrong.
A day on the moon is about 29 earth days. Building around the equator would ensure 50% of the panels are always receive sunlight.

Tide Locked (1)

gd2shoe (747932) | about 5 months ago | (#46319911)

Yes, but it's not always the same half. :-P

The moon is tide-locked to the Earth, not to the sun. The so-called "dark side of the moon" gets just as much sunlight, but it never faces us. Moon based solar collection will have most of the problems that Earth based collection has... and a whole host of new problems.

Re:Solving the wrong problem (1)

SJHillman (1966756) | about 5 months ago | (#46319771)

We get plenty of sunlight, but 70% of that is over ocean. Even over land, there's a lot of places that don't get good sun coverage but still get to see the moon every day/night (e.g. higher latitudes)

is that really better than earth based? (4, Insightful)

hawguy (1600213) | about 5 months ago | (#46319551)

Solar insolation on the moon is not dramatically higher than on Earth - around 1400 W/m^2 versus around 1000 W/m^2 on Earth. Granted, a Lunar solar station wouldn't be affected by weather, but Earth based receivers will suffer from efficiency loss during bad weather.

Could they achieve the same result by building a bit larger system on earth, but without the hundreds (or thousands?) of rocket launches it would take to get the materials to the moon to get the thing started?

Besides, who wants to see a big black ribbon around the moon?

Re:is that really better than earth based? (1)

cnettel (836611) | about 5 months ago | (#46319615)

Solar insolation on the moon is not dramatically higher than on Earth - around 1400 W/m^2 versus around 1000 W/m^2 on Earth. Granted, a Lunar solar station wouldn't be affected by weather, but Earth based receivers will suffer from efficiency loss during bad weather.

Could they achieve the same result by building a bit larger system on earth, but without the hundreds (or thousands?) of rocket launches it would take to get the materials to the moon to get the thing started?

Besides, who wants to see a big black ribbon around the moon?

They plan to use lunar materials, so no hundresds of rocket launches to get started. I guess the point is kind of that real estate and raw materials are "free", if you get the proper manufacturing equipment up there. If that equipment is automated enough, you can build up slowly, but steadily.

Re:is that really better than earth based? (2)

wisnoskij (1206448) | about 5 months ago | (#46319791)

I think you are under estimating the amount of machinery it takes to turn a mountain of rock, dirt, and minerals into a field of solar panels. The infrastructure required for that would likely eclipse the 11,000 KM stripe of solar panels.
If you wanted to manufacture sophisticated stuff like that on the moon, you would need it to be as the last step of a 200 year plan to start mining/industry/living on the moon.

Re:is that really better than earth based? (1)

Areyoukiddingme (1289470) | about 5 months ago | (#46319843)

If you wanted to manufacture sophisticated stuff like that on the moon, you would need it to be as the last step of a 200 year plan to start mining/industry/living on the moon.

Let's do THAT. And build the world-girdling strip of solar panels, all tied together with superconductors (easy to use, on the Moon), and use that power on the Moon for the burdgeoning civilization we're building there. Forget beaming it at Earth.

Re:is that really better than earth based? (0)

Anonymous Coward | about 5 months ago | (#46319935)

Troll is not a replacement for I disagree.

It does if you disagree with a troll. [ducks and hides]

Re:is that really better than earth based? (1)

hawguy (1600213) | about 5 months ago | (#46319947)

Solar insolation on the moon is not dramatically higher than on Earth - around 1400 W/m^2 versus around 1000 W/m^2 on Earth. Granted, a Lunar solar station wouldn't be affected by weather, but Earth based receivers will suffer from efficiency loss during bad weather.

Could they achieve the same result by building a bit larger system on earth, but without the hundreds (or thousands?) of rocket launches it would take to get the materials to the moon to get the thing started?

Besides, who wants to see a big black ribbon around the moon?

They plan to use lunar materials, so no hundresds of rocket launches to get started. I guess the point is kind of that real estate and raw materials are "free", if you get the proper manufacturing equipment up there. If that equipment is automated enough, you can build up slowly, but steadily.

That's why I started at the low end of "hundreds of launches" -- if raw materials were needed, launches would be in the many thousands or tens of thousands. Unless aliens left us a manufacturing plant on the moon when they buried the monolith [youtube.com] , it's going to take a lot of equipment to get started.

Construction of the ISS required over 40 assembly launches. [seds.org] . And those launches were all to LEO which allows much bigger payloads than launching to the moon.

Perhaps the future will bring more efficient ways to get materials off the earth, but so far we're reliant on rockets.

Think back to (1)

AHuxley (892839) | about 5 months ago | (#46319701)

Strategic Defense Initiative (Star Wars) http://en.wikipedia.org/wiki/S... [wikipedia.org]
The US contractors and gov spend time and treasure looking at different forms energy over distance in space.
Something very expected happens over distance to all that power, then add in the earths weather and you have non trivial issues.
Add ever more power or lasers or wavelengths... it all drops off fast but finding out just how and by how much can be a wonderful boondoggle.
Interaction of multiple lasers, different rays, microwaves all have their power, distance issues and are known to science.

Re:is that really better than earth based? (0)

Anonymous Coward | about 5 months ago | (#46319827)

40% isn't dramatically higher?

Re:is that really better than earth based? (1)

hawguy (1600213) | about 5 months ago | (#46319905)

40% isn't dramatically higher?

Not when it's 240,000 miles away and you need to escape the Earth's large gravity well to get there.

How far would you be willing to drive to save 40% on something? Would you be willing to drive around the world 10 times to get a 40% better deal?

Re:is that really better than earth based? (1)

beelsebob (529313) | about 5 months ago | (#46319917)

Not when the loss from beaming the energy back will be in that region, no.

Transmetropolitan (1)

o_ferguson (836655) | about 5 months ago | (#46319555)

So then this world will be like Transmetropolitan, only lamer, because it's on the Moon and not Mercury...

FTFY (1)

jklovanc (1603149) | about 5 months ago | (#46319581)

Some of the company's other projects look just as luicrous.

Re:FTFY (3, Informative)

aitikin (909209) | about 5 months ago | (#46319623)

Some of the company's other projects look just as ludicrous.

Helps when you put the D in there.

Re:FTFY (5, Funny)

Qwade79 (2464458) | about 5 months ago | (#46319765)

Helps when you put the D in there.

That's what she said ... heh heh heh

.... I'll get my coat.

bad bad idea (0)

Anonymous Coward | about 5 months ago | (#46319589)

we're already warming, no need to pump in extra energy. we need to use the plenty we get from the sol better.

Re:bad bad idea (1)

beelsebob (529313) | about 5 months ago | (#46319921)

On the contrary, pumping extra energy in in a way that allows the energy to escape again is orders of magnitude better than pumping out gasses that prevent the energy from escaping.

Re:bad bad idea (0)

Anonymous Coward | about 5 months ago | (#46320011)

its not either or.

this is misdirecting effort. smart people solving a problem that doesn't exist. we use energy we get better we don't need to pump more from the moon.

like i said, bad idea.

Re:bad bad idea (3, Interesting)

Immerman (2627577) | about 5 months ago | (#46320025)

It's not the energy we use that does the warming - the CO2 released from burning fossil fuels captures about a million times as much solar energy per year as there was energy in the fuel, and it does so for many decades before leaving the atmosphere.

Gravity wells and other distance issues (5, Informative)

JoshuaZ (1134087) | about 5 months ago | (#46319593)

A major issue is that the moon is fairly far up Earth's gravity well. It is easy to get things to low-Earth orbit and already tough to get things to even geo-stationary. The main saving of putting anything on the moon will come if you can do a large part of your construction on-site since otherwise moving that much material up is going to be tough. If you are doing automated construction on site you also are going to need to be able to make mainly a lot of solar cells. Solar cells are primarily silicon and there's already been prior research on refining the moon's regolith for silicon to manufacture electronic components and that looks possibly doable but one does need to get over some technical chemistry issues. See e.g. http://www.asi.org/adb/02/13/02/silicon-production.html [asi.org] .

The other issue is distance for power transmission: most designs for microwave power involve power transmission from at most a little over geo-stat at about 35,000 km. The distance to the moon is about 10 times that, so if you don't have a really tight beam, there are going to be issues. Also, since the moon change's position you are going to need a large number of sites on Earth that can receive the beam, and if you can't switch off smoothly between them always (which would itself require massive planet-wide infrastructure), you would still need power sources on Earth (possibly just massive storage facilities?) to deal with those times.

Overall, a really cool idea with a lot of technical hurdles. I hope they can make it work but I'm not optimistic.

Re:Gravity wells and other distance issues (2)

JoshuaZ (1134087) | about 5 months ago | (#46319605)

Ok. I just looked at their plan in more detail (that is read all of TFA). They are planning on getting the solar panels and most other infrastructure from Earth. That means massive costs in terms of riding up the gravity well. This makes their plan look extremely implausible.

Re:Gravity wells and other distance issues (1)

cnettel (836611) | about 5 months ago | (#46319647)

Go to the company website instead. They say lunar resources and are able to tell the difference between kms and miles. However, it's all a bit pie in the sky even there. Even with the advantage of lunar resources, I would be more optimistic about geostationary orbital solar power. Microgravity would mean that you could get away with really thin structures, even concentrated thermal solar might make sense if you can work out a reasonable cooling part of the cycle (just make an extremely thin mirror as the bulk of the concentrator).

Re:Gravity wells and other distance issues (1)

Immerman (2627577) | about 5 months ago | (#46320087)

I suspect cooling would be a much larger challenge on the moon - no fluids to transport environmental heat away, so you're limited to dumping it into the rock (how fast can heat conduct through lunar rock?) or radiating into space. Plus the whole "moving parts need maintenance" issue is going to be a lot harder to deal with on the moon.

The concentrated solar is a good idea though, no reason it couldn't be combined with photovoltaics instead. With no winds to deal with you could potentially just use a thin mylar sheet suspended along the long edges edges. It'd default to a catenary curve rather than parabolic, but that's awful close, and slightly changing the lateral thickness/mass distribution would let you fine-tune the curve however you saw fit. The only problem I see with solar concentrators is that if there's any "slop" then you may end up reflecting a lot of sunlight towards the Earth. Considering that the moon's surface is roughly coal-black that could make for some really annoyingly bright flashes in comparison.

Re:Gravity wells and other distance issues (1)

Blaskowicz (634489) | about 5 months ago | (#46319877)

Also, since the moon change's position you are going to need a large number of sites on Earth that can receive the beam, and if you can't switch off smoothly between them always (which would itself require massive planet-wide infrastructure), you would still need power sources on Earth (possibly just massive storage facilities?) to deal with those times.

That is funny. If you have massive storage facilities, preferably extremely cheap and relatively innocuous to the environment, then you've solved the whole electrical power problem already. Current wind and solar generation are atrocious because of the lack of such storage.

Re:Gravity wells and other distance issues (1)

CrimsonAvenger (580665) | about 5 months ago | (#46320003)

It is easy to get things to low-Earth orbit and already tough to get things to even geo-stationary.

Note that, excluding the landing part, it takes about 10% more deltaV to reach lunar orbit than to reach geosynch orbit.

Re:Gravity wells and other distance issues (1)

JoshuaZ (1134087) | about 5 months ago | (#46320055)

That's a good point, so from a strict get-there-once attitude this won't be so bad. However, I don't think that slamming into the moon is going to be a good strategy here unless they used some sort of extremely robust system which would create its own problems.

Re:Gravity wells and other distance issues (0)

Anonymous Coward | about 5 months ago | (#46320007)

There was a Nasa study on geostationary solar power satellites. They had a design for simple to build satellites each providing 1 GW and studied the costs involved in a program that put up one of those every year. Even including transportation costs, including humans for maintenance and assembly being rotated up and down (this was from the 70s or so) after a few satellites (5? 10? I don't recall) it was cheaper to mine the materials on the moon and assemble everything in orbit than it was to lift everything from earth.

I remember they had a simple design with klystrons and rectennas for power transmissions and old school low efficiency solar panels, nowhere near cutting edge, that could be made from lunar materials and it was still cheaper to just mine them there and send up people to work the factories to assemble them.

Nowadays with robots and telepresence you could probably do it cheaper. Personally I liked that plan a lot because it gets us away from space exploration and tourism into real space industries. But the cost per GW was prohibitive back then.

Awesome! (1)

Zitchas (713512) | about 5 months ago | (#46319607)

Are these ideas realistic anytime soon? Not really. Are they possible with today's technology? Iffy, although some probably are. Would I like to see most of them actually in existence now, if it were possible? Most definitely!

Especially the space ones, and the pyramid city. I like those ideas!

Anonymous Grammar Nazi (0)

Anonymous Coward | about 5 months ago | (#46319637)

"Its way"... not "It's way".

What could possibly go wrong.... (0)

Anonymous Coward | about 5 months ago | (#46319657)

Whoops, we just microwaved the south pacific, boiling the seas creating the largest fish soup bowl in the world.

Re:What could possibly go wrong.... (0)

Anonymous Coward | about 5 months ago | (#46319717)

so tired of the AC what could possibly go wrong posts with every new technology talked about here

i fear the next generation will move us technologically backwards when they take power given this seems to be the prevailing attitude

and i propose we nuke the moon into oblivion (1)

maliqua (1316471) | about 5 months ago | (#46319697)

i feel that my proposal is just as likely to become a reality be it a good idea or not

Re:and i propose we nuke the moon into oblivion (0)

Anonymous Coward | about 5 months ago | (#46320099)

Sorry you are too late, plan A119 plan already seriously proposed by the US military a good couple decades ago. Anyway, you were saying...?

Shades of Gundam X... (1)

RyuuzakiTetsuya (195424) | about 5 months ago | (#46319711)

Microwave power plant on the moon?

What's next, giant energy beam cannon powered by said power plant?

Re:Shades of Gundam X... (1)

Ashe Tyrael (697937) | about 5 months ago | (#46319825)

I rather doubt they'll be able to implant a newtype in it, however.

Focus (1)

Dereck1701 (1922824) | about 5 months ago | (#46319809)

Perhaps they should focus on one incredibly ambitions plan instead of eight separate ones. I'm also a bit curious how big the receivers would have to be earthside to collect the beamed energy. I don't know if they've invented the microwave equivalent of a laser which is probably what would be needed to to keep the receivers less than 20 miles wide.

Re:Focus (1)

techno-vampire (666512) | about 5 months ago | (#46320051)

I don't know if they've invented the microwave equivalent of a laser...

As it so happens, the maser [wikipedia.org] was invented several years before the laser, and the laser was originally called an "optical maser."

Re:Focus (1)

kenwd0elq (985465) | about 5 months ago | (#46320129)

Actually, the MASER was invented first; they only managed to do it with light later.

One Day This Will Be Done (1)

Crypto Gnome (651401) | about 5 months ago | (#46319855)

Whether it's specifically THIS project, or another.

Whether it's The Japanese or someone else.

The incentive to achieve this is too unavoidable.

Why? (I hear you ask)

Because the distinction between a targetable multi-terawatt laser and an eco-friendly solar-power downlink is mythical (legal, at best).
So Japan can bypass (simultaneously, no less) their own constitutional ban on militarisation AND the internal treaty against "space weapons".

Re:One Day This Will Be Done (0)

Anonymous Coward | about 5 months ago | (#46320117)

It will never happen, ever. How you like that?

Going up. (1)

Orleron (835910) | about 5 months ago | (#46319875)

I'm sure they will do this as soon as a space elevator becomes available. I probably wouldn't hold my breath.

Re:Going up. (0)

Anonymous Coward | about 5 months ago | (#46320083)

If we had the energy and resources to build that fantasy, why would we need electricity from the Moon?

We all know where this is going. (1)

jtownatpunk.net (245670) | about 5 months ago | (#46319897)

William Atherton better have his home insurance paid up.

Just trun on no disasters and you will be fine (1)

Joe_Dragon (2206452) | about 5 months ago | (#46319933)

But with them off nukes cost less and give off more power.

Complete utter fucking nonsense (0)

Anonymous Coward | about 5 months ago | (#46319937)

Start by building the Solaren plant in orbit first you Space Nutter religious fundamentalists. You swindlers.

Are they crazy? (1)

Hamsterdan (815291) | about 5 months ago | (#46319965)

Guess they never played SimCity...

Dr. David R Criswell and Shimizu (4, Informative)

Baldrson (78598) | about 5 months ago | (#46319967)

Actually, lunar-based solar power for Earth is decades old, and was first patented [google.com] by Dr. David R. Criswell [lunarsolarpower.org] in the late 80s. I was working for Dr. Criswell at the California Space Institute in La Jolla in 1985 while he was developing this idea so I know it goes back at least to the mid 80s.

Shimizu Corporation intersects with Dr. Criswell in another way that I just discovered today after searching for his more recent patents.

We've got to attract technological civilization's population away from natural ecosystems into idealized artificial environments such as Shimizu Corporation's design for what it calls the "Green Float" [shimz.co.jp] . You can house the entire population of civilization in beach-front property on the boundary of a tropical rain forest where people can swim, fish, hunt and gather recreationally, as well as access the height of urban lifestyle. From there space habitats are likely to emerge so that the natural propensity of these "cells" to replicate endlessly needn't destroy Earth's biosphere. Interestingly, I came up with a geometry that looks very similar to that years ago, with the Solar Updraft Tower Algae Biosphere proforma [oocities.org] and, over the subsequent years, I found a floating photobioreactor technology that requires little more than 2 layers of polyfilm that has demonstrated production per cost figures far in excess of what I projected in that proforma. Before I ran across Shimizu Corp's Green Float I had further refined the idea based on the Atmospheric Vortex Engine [blogspot.com] , which, like Shimizu's "Green Float", is ideally sited in the equatorial doldrums and could make use of the central tower of the Green Float. I posted some preliminary thoughts over at the Seastead Institute's blog [seasteading.org] .

A key problem I attempted to address in my preliminary thoughts was the early market for energy from the Atmospheric Vortex Engines that would form the nuclei for Shimizu's Green Floats. A big problem was the fact that the electric power markets are thousands of miles away from the floating AVEs even if you could build on the order of a terawatt of oceanic power transmission lines thousands of miles long. Early markets are critical for attracting capital -- the lack of which renders such grandiose ideas "non-starters".

I had thought it would be very nice to have a microwave transmission technology that could dynamically switch the power distribution to achieve the holy grail of "dispatchable [wikipedia.org] " power generation for peak loads, but wasn't aware, until just now, that Dr. Criswell's recent revision of his patent [google.com] serves precisely that purpose.

Too small (0)

Anonymous Coward | about 5 months ago | (#46320091)

It's a grand idea, but too limited. I'm still waiting for a proposal along the lines of Transmetropolitan, covering the surface of Mercury with solar panels.

Why on the Moon? (1)

kenwd0elq (985465) | about 5 months ago | (#46320119)

Why on the surface of the Moon? That's nonsense. In case they hadn't thought about that, the nights on the Moon are 14 days long; why go into space to achieve the same problems we have right here on Earth?

Build them in orbit. First of all, they won't need to be sturdy enough to hold up under their own weight, and can be in the sun 99% of the time. Second, beaming power back from 22,000 miles up will be easier than beaming it back from 250,000 miles.

Re:Why on the Moon? (1)

kenwd0elq (985465) | about 5 months ago | (#46320149)

Besides, it we're going to go to the Moon for power, I think Harrison Schmitt's plan to mine He3 from the surface and ship it back to fuel our fusion powerplants.

https://en.wikipedia.org/wiki/... [wikipedia.org]

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